Oxygen in Hood Canal bounces back overnight

Conditions have remained pretty much the same the last couple of
days, although the intrusion of dense higher-oxygen water from the
ocean is beginning to create a thicker layer at the bottom of Hood
Canal. The middle layer of low-oxygen water remains fairly thick,
but the upper layer with higher oxygen concentrations is still
providing fish some relief. South winds remain a threat, as I’ve
explained for the last few weeks.

One can observe the three layers in the upper graph. The lower
graph shows changes over the past week or so. Notice how oxygen
concentrations are rising in the deep layer.

—–

Fish in southern Hood Canal got a little more room to breathe
this morning, as oxygen levels rose in the top 30 feet of the water
column.

Many spot prawns died
Tuesday near Hoodsport Hatchery while swimming into fresh water to
get oxygen.Photo by Wayne Palsson, WDFW

I described the latest observations from researchers in a story
published this morning on the
Kitsap Sun’s website. A story written for
today’s Kitsap Sun also contains some important observations
about events of the past two days.

The rapid recovery may have been largely the result of a seiche,
in which waters pushed away by winds came back when the winds
ceased. In terms of the overall conditions, nothing major has
changed, however, and south winds could trigger another fish
kill.

One thing I found interesting but disturbing was that many of
Hood Canal’s famous spot prawns were making a deadly choice. They
were swimming into freshwater inlets, where the waters were more
oxygenated, only to die when they could not survive the low
salinity. I understand that the greatest losses were at the outlet
of the lower Cushman Dam at Potlatch, where waters from the North
Fork of the Skokomish River come into Hood Canal.

Here’s how the oxygen levels have changed at Hoodsport
since 11 o’clock last night and 10 o’clock this morning. Note the
blue line, which is about the 9-foot level, as measured by a
monitoring buoy that operates around the clock.

Poaching of fish, shellfish and wildlife is a serious problem throughout Washington state, as Rich Jacobson points out in his blog post. State enforcement officers have never been able to keep up with all the illegal activity, and the number of officers has been continually reduced by state budget limitations.

If you read the enforcement report mentioned in the blog, you’ll see that illegal activities are committed by both tribal and nontribal fishermen, sport and commercial, as well as hunters. Officers tell me that impacts on the resource are serious, but actual quantities of fish and shellfish taken illegally cannot be assessed because most violations are never reported.

Hmmm, maybe we ought to put more money into enforcement and less money into never-ending research and advocacy. Seems to be a much bigger impact than the occasional south wind. Likewise… I noticed a bit of investigative journalism when a Navy ship was suspected of impacting a few oysters. Any chance you’re gonna turn that zeal toward this?

Conditions in Hood Canal have remained pretty much the same the last couple of days, although the intrusion of dense higher-oxygen water from the ocean is beginning to create a thicker layer at the bottom of Hood Canal. The middle layer of low-oxygen water remains fairly thick, but the upper layer with higher oxygen concentrations is still providing fish some relief. South winds remain a threat, as I’ve explained for the last few weeks.

One can observe the three layers in the upper graph. (See top of this entry.) The lower graph shows changes over the past week or so. Notice how oxygen concentrations are rising in the deep layer.